var mysql = require('mysql');
var {pool} = require('./config')

const operation = (sql) => {
    // 在请求之前建立一个新的请求，防止报错Cannot enqueue Handshake after invoking quit（调用Quit后无法排队握手）
    pool = mysql.createConnection(pool.config);
    pool.connect();
    return new Promise((resolve, reject) => {
        pool.query(sql, (err, result) => {
            if (err) return err;
            resolve(result)
        })
        pool.end()
    }).then(res => {
        return res[0]
    }).catch(err => {
        return err
    })
}

module.exports = {
    operation
}

